A Flat,horizontal Uniform Plank Is Supported Underneath by a Triangular

Multiple Choice

A flat,horizontal uniform plank is supported underneath by a triangular wedge which itself rests on flat,level ground.An object that has the same weight as the plank is placed on the left end of the plank.Where must the wedge be placed under the plank in order for the system to be in equilibrium?

A) 1/6 the length of the plank from the left end
B) 1/5 the length of the plank from the left end
C) 1/4 the length of the plank from the left end
D) 1/3 the length of the plank from the left end